Stl format is obsolete: here’s why you should be using 3mf

STL format is ancient in computer terms, as it was first released in 1987 by 3D systems. STL files were designed with additive manufacturing in mind, translating design data, typically NURBS or BREP based, into a mesh for 3D printers to interpret. With that context in mind, it makes a lot of sense why STL format was created to begin with — translating curves and compound surfaces into machine data would be an astronomical amount of code to run.

Some people still experience faceted prints of their parts because STLs interpret your data and essentially create a facsimile of your part, not an accurate representation. Have you ever wondered why your STL can sometimes be as much as 10x the file size of your original file? Well, STLs are a mesh-based architecture, so they cannot store information as a mathematical representation. Therefore, only raw information can be carried over. That is the essence of why they are so massive, inconvenient, and destructive to your geometry.

Additionally, STLs do not carry any machine information, settings for printing, or any other helpful information needed to recreate the file. As a result, we need to attach STLs with a list of manufacturing specifications when working with a team or a third party to get a part made.
IF STL format is so terrible, why do we use it? There are three answers:

⦁ STL is still the standard file format for many users.
⦁ 3D printers only support mesh-based files in their slicers.
⦁ Many people are unaware of alternatives.

Enter 3MF, a file format developed by a consortium of companies working together to advance 3D printing capabilities and technologies.

What makes 3MF files revolutionary and special enough to abandon STL files? The improvements that 3MF brings to the table are equivalent to switching from BMPs to PDFs. For one, 3MF files carry way more information, including unit information, color and texture information for multijet prints, relative position in space, and so much more. STLs do not even have units! Even though they carry this much data, 3MF files are still significantly smaller than STL files.


Yeah, this paper is an advertisement for Fusion 360. Can you open a 3MF file in the more "hobby user " range tools?

HI Julie

Welcome to the Forum. Glad to see you here.

Personally I have never used 3MF style files before, I stay with what I have known in the past. Seems like STL is pretty well the standard. There will always attempts to improve on it though.